The present invention relates to the exhaust gas emitted from a turbomachine, and more particularly to a system and method of utilizing a turbomachine as a prime mover of the exhaust gas recirculated within an EGR system.
There is a growing concern over the long-term effects of Nitrogen Oxides (hereinafter NOx) and Carbon Dioxide (hereinafter “CO2”) and Sulfur Oxides (SOx) emissions on the environment. The allowable levels of emissions that may be emitted by a turbomachine, such as a gas turbine, are heavily regulated. Operators of turbomachines desire methods of reducing the levels of NOx, CO2, and SOx emitted.
Significant amounts of condensable vapors exist in the exhaust gas stream. These vapors usually contain a variety of constituents such as water, acids, aldehydes, hydrocarbons, sulfur oxides, and chlorine compounds. Left untreated, these constituents will accelerate corrosion and fouling of the internal components if allowed to enter the turbomachine.
Exhaust gas recirculation (EGR) generally involves recirculating a portion of the emitted exhaust stream through an inlet system of the turbomachine. The exhaust stream is then mixed with the incoming airstream prior to combustion. The EGR process facilitates the removal and sequestration of concentrated CO2, and may also reduce the NOx and SOx emission levels. The recirculated exhaust mixes with the incoming airstream to create an inlet fluid. The exhaust stream should be adequately mixed with the airstream within a portion of the inlet section.
For the foregoing reasons, there is a need for an inlet system that allows for integration with the EGR system. The inlet system should direct the recirculated exhaust stream in a manner that allows for mixing with the incoming airstream.